how to use laser thermometer

[lenarenee]

Before I attempt to make more candles or lotion, can somebody tell me how to use them correctly?

For instance, when temping oil the red light penetrates right through the oils to the bottom - so how do you know it the temp reading is oil, or metal surface?

And why can't you get matching temp readings when reading is taken 5 seconds apart? Makes me think the thermometer is off or I just don't know what I'm doing!

 

[dillsandwitch]

I was just making some melts and I used the thermometer the same way that I use it when I'm making home brew. Not sure if its the correct way to use it but it hasnt failed me yet.

If the container is opaque then I just shine the beam right through the side in about the middle.

As for the changing temps my guess is that its cause the wax is cooling pretty fast.

 

[CaraBou]

My understanding is they measure the surface temp. It is important to shoot the beam from the right distance, because the instrument measures an area based on distance that the beam traveled; they don't just measure a point. Your owner's manual should tell you how to get the right distance. If your readings are varying, could it be because you have varied the distance?

 

[gemsupthepoley]

Mine has a picture on the side giving distances etc.

 

[Steve85569]

They are infrared sensors.
The only measure light energy in the infrared range (heat) given off by an object. The internal temperature can be considerably higher or lower depending on the situation.
They are great for giving you an instant approximation of somethings temperature. If you want to be really precise either a "k" or" "j" type probe is much more accurate but takes a lot longer and is an invasive probe.

Take multiple readings from top and sides and use a rough average of them. Mainly watch for temps that are too high or just "outliers".

 

[The Efficacious Gentleman]

And stir if possible just before reading, so that the heat is evenly distributed

 

[lenarenee]

Thanks everyone. Sounds like I should get a "real" thermometer for making lotion for the heat and hold process. Screwing up a candle only gives you a less effective candle but for a lotion I'll want something more precise.